- Published 2014 in Physical review letters

We formulate the work output and efficiency for linear irreversible heat engines working between a finite-sized hot heat source and an infinite-sized cold heat reservoir until the total system reaches the final thermal equilibrium state with a uniform temperature. We prove that when the heat engines operate at the maximum power under the tight-coupling condition without heat leakage the work output is just half of the exergy, which is known as the maximum available work extracted from a heat source. As a consequence, the corresponding efficiency is also half of its quasistatic counterpart.

@article{Izumida2014WorkOA,
title={Work output and efficiency at maximum power of linear irreversible heat engines operating with a finite-sized heat source.},
author={Yuki Izumida and Koji Okuda},
journal={Physical review letters},
year={2014},
volume={112 18},
pages={180603}
}